A novel photocatalytic membrane decorated with RGO-Ag-TiO2 for dye degradation and oil-water emulsion separation

BACKGROUND: Membrane separation is a promising process for treatment of dye and oily wastewater if the antifouling capacity and recyclability can be improved. In recent years, the development of photocatalytic materials has provided new methods for research into membrane technology. RESULTS: In this study, a novel photocatalytic membrane decorated with RGO-Ag-TiO2 nanomaterial was fabricated by simple vacuum filtration for degradation of dye and separation of oil-water. First, TiO2 nanowires were prepared for more effective photocatalysis, reduced graphene oxide (RGO)-Ag-TiO2 was fabricated by a facile hydrothermal reaction, then it was directly decorated on cellulose acetate (CA) membrane using polyethylene glycol and glutaraldehyde. CONCLUSION: The as-prepared photocatalytic membrane can simultaneously degrade dye and separate oil-water emulsions under visible-light irradiation in a short time. The membrane has extremely high water flux (191 L m(-2)h(-1)) and rejection rates (almost 100%) of dye-oil-water emulsion. More importantly, the photocatalytic membrane shows excellent antifouling capacity and recyclability, and retains relatively stable dye-oil-water permeation flux (about 27.5 L m(-2)h(-1)) and high rejection rates (up to 99%) after six cycles of experiments under visible-light irradiation. Overall, the photocatalytic membrane opens up new avenues for the treatment of wastewater. (c) 2017 Society of Chemical Industry